DIY NAS for Infuse/ATV4K

I’m looking for a solution to play local videos (currently on a 6TB USB3 hard drive) on a 4K TV. Ideally through Apple TV 4K via Infuse.

I don’t have a NAS and since the hard drive is relatively new and expensive (G Tech), I don’t want to buy a NAS enclosure. Especially as I could circumvent the issue by getting a Nvidia Shield and connect over USB.

To get my content onto the ATV4K, I need some sort of networked solution. But what are the requirements?
Will a Raspberry Pi solution work?
Are there Pi-like boards with USB3?
I don’t need content anywhere else. Does that mean I don’t need 4K transcoding?

Raspberry Pi is a joke for a NAS, it has a shared Ethernet bus with USB. Even the new one doesnt support full gigabit speed.

Behold my consolidated (2 into 1) Xeon NAS

Some routers allow for an attached USB drive that can be shared.

If you are looking for such I’d consider the ODROID-XU4… it’s around the same price and its CPU and networking is x times faster. For some gory details…
http://www.avsforum.com/forum/76-htpc-linux-chat/2581649-75-server-media-client.html